Old name of Bangladesh. East Pakistan was a wing of Pakistan and along with West Pakistan formed the country of Pakistan. But unfortunately the politicians of West Pakistan committed crimes against the people of East Pakistan. This ended up in East Pakistan separating.
If East Pakistan was still part of Pakistan, Pakistan would have been a better and more successful country but alas!

Unfortunately East Pakistan separated from Pakistan because of the mass killings of people in East Pakistan. I am sorry for all the loses. A Pakistani